istringstream

When would I use std::istringstream , std::ostringstream and std::stringstream and why shouldn't I just use std::stringstream in every scenario (are there any runtime performance issues?). Lastly, is there anything bad about this (instead of using a stream at all): std::string stHehe("Hello "); stHehe += "stackoverflow.com"; stHehe += "!"; CB Bailey Personally, I find it very rare that I want to perform streaming into and out of the same string stream. Usually I want to either initialize a stream from a string and then parse it; or stream things to a string stream and then extract the result

I have a code for reading files with float numbers on line stored like this: "3.34|2.3409|1.0001|...|1.1|". I would like to read them using istringstream, but it doesn't work as I would expect: string row; string strNum; istringstream separate; // textovy stream pro konverzi while ( getline(file,row) ) { separate.str(row); // = HERE is PROBLEM = while( getline(separate, strNum, '|') ) { // using delimiter flNum = strToFl(strNum); // my conversion insertIntoMatrix(i,j,flNum); // some function j++; } i++; } In marked point, row is copied into separate stream only first time. In next iteration it